Typewriter



June 17, 1924. 1,497,977

. o. A. HOKANSON TYPEWRITER Filed June 5, 1920 3 Sheets-Sheet 1 June 171924.

O. A. HOKANSON TYPEWRITER Filed June 5 1920 5 Sheets-Sheet 2 June 17,1924. 1,497,977

0. A. HOKANSON TYPEWRITER 3 Sheets-Sheet 3 Filed Juno 5, 1920 5 (w; a.7m

Patented June 17, 1924.

NITED STATES 1,497,977 PATENT OFFICE.

OTTO A. HIOKANSON, OF WOODSTOCK, ILLINOIS, ASSIGNOR TO vWOODSTOCK TYPE-WRITER COMPANY, OF WOODSTOCK, ILLINOIS, A CORPORATION OFILLINOIS.

TYPEWRITER.

Application filed June 5, 1920. Serial No. 386,887.

I '0 all whom it may concern Be it known that I, OTTO A. HoKANsoN, acitizen of the United States, and a resident of Woodstock, in the countyof Mo- Henry and State of Illinois, have invented certain new and usefulImprovements in Typewriters, of which the following is a specification.

This invention relates generally to typewriter mechanism and moreespecially to line lock and signal mechanism for controlling theoperation of the typewriter as the platen approaches the limit of itsmove ment.

The invention has for its object the provision of mechanism of thecharacter named which shall be of improved construction and operation,and it is exemplified in the combination and arrangement of parts shownin the accompanying drawings and described in the followingspecification'and is more particularly pointed out in the appendedclaims.

In the drawings,

Fig. 1 is aside elevation ,of a portion of a typewriter having oneembcdimentof the present invention applied thereto;

Fig. 2 is a fragmentary top plan view of a portion of the mechanismshown in Fig. 1;

Fig. 3 is a horizontal section substantially on line 33 of Fig. 6;

vFig. 4 is a fragmentary vertical section substantially on line 4-4 ofFig. 3;

Fig. 5 IS a sectional view on line 5-5 showing a detail of construction;and

Fig. 6 is a vertical section substantially on line 6-6 of Fig. 3.

Fig. 7 is a fragmentary front elevation of the universal bar and typebar guide. While the present invention is applicable to various forms oftypewriters, it is especially adapted for use in connection with atypewriter having a folding platen carriage support and is shown in thedrawings as applied to such a form of typewriter. In the embodiment ofthe invention illustrated the numeral 10 designates the base frame ofthe typewriter having a pair of arms 11 pivoted at 1'2 thereon forsupports ing the platen carriage frame. A platen carriage base, plate 13is secured to the arms 11 adjacent their ends and a platen carriage 14is mounted on the base 13 to travel longitudinally thereof. The movementof the platen carriage is controlled by an escarria e.

capement wheel 15 having a pinion 16 meshing with a rack 17 connectedwith the platen The escapement wheel 15 is controlled by a dog rocker 18pivoted on a bracket 19 connected with the lower faceof a supportingplate 20 secured to the lower surface of the platen carriage frame 13.

- The dog rocker 18 carries a fixed dog 21 and a movable dog 22 and isoscillated by.

a plate 23 which forms the lowerarm of a bell crank lever having anupwardly extending arm 24 extending into the path of movement of thetype bars. When the arm 24 is struck by a type bar, it is move-d to theright, as viewed in Fig. 6, thus swinging the plate 23 downwardly. l Theplate 23 carries a tongue 25 which engages a tail piece 26 connectedwlth the dog rocker 18.

The movement of the plate 23 will therefore swing the dog rocker 18downwardly to shift the contact wvith the escapement wheel 15 from themovable dog 22 to the fixed dog 21. When the type bar rebounds the arm24 returns to its initial position and the dog rocker 18 isalso'returned to position by a spring 27, thus freeing the escapement'wheel 15 and permitting it to rotate until it is stopped by'engagementwith the movable dog 22. a Q

When the platen nears the limit of its movement, it is desirable toautomatically prevent further operation of the type upon the paper andthis is done by controlling the arm 24 so that when it is struck by atype bar, it will not move rearwardly to permit the type to strike theplaten, but

will be held in the position shown in Fig 8 and thus stop the movementof the type bar before an impression is made upon the paper. Themechanism for holding the arm 24 in locked position is controlled by astop 28 adjustably mounted ona margin stop irangedto engage notches 35in the bar 29.

The stop 28 may be adjusted along the bar 29 by pressing downwardly on afinger piece 36 to free the lug 34 from the notches 35, and when the baris moved to the desired position, the spring 33 will automaticallyreengage the lug 34 with one of the notches 35. An arm 37 extendsdownwardly from the stop 28 and carries a foot plate 38 beveled at oneedge, as shown at 39. A pin 40 is carried by the foot plate 38 andextends downwardly as shown in Figs. 1 and 4.

A bell crank lever 41 is pivoted at 42 on the lower face of the platencarriage bed plate 13 and is provided with an upwardly bent flange 43which extends into the path of movement of the foot piece 38 on the,stop 28. The bell crank 41 has a slot 44 formed therein for limiting themovement thereof and is also provided with a disc-shaped bearing 45which co-operates with the bifurcated, end of an arm 46 on a bell cranklever 47 pivoted at 48 on the plate 13. An

arm 49 of the bell crank lever 47 projects forwardly and carries, a link50 pivoted at 51 to the forward end of the arm 49. The end. of the link50 opposite its pivotal connection 51 is provided with a hook 52extending upwardly through a slot 53 in the bracket 13, as shown inFigs. 5 and 6, so that the nose piece of the hook 51 rests upon theupper face of the plate 13 and supports the end of the link 50. A flange54 projects forwardly from the lower edge of the link 50 so that in oneposition of the link the flange extends beneath the arm 23 of theuniversal member 24, as shown in Figs. 5 and 6. When the flange 54 isin'this position the arm 23 will be locked against downward movement sothat when the universal member 24 is struck by the type bars it willstop the movement of the bars before the type engage the platen. In thisposition of the link 50 the dog rocker 18, will also be held againstmovement since the dog rocker is connected with the plate 23 by the tailpiece 26. A spring 55 is connected with the bell crank lever 41, asshown in Fig. 3, and normally holds the link 50 in a retracted positionso that the flange 54 is disengaged from the plate 23 leaving the platefree to operate. When, however, the platen carriage approaches the endof its movement the foot plate 38 will strike the contact member 43 ofthe bell crank 41 and shift the bell cranks- 41 and 47 and the link 50into the position shown in Figs. 5 and 6 so that the universal member 24will be locked preventing tun ther writing or movement of the platen.

If it is desired to release the line locking mechanism, in order toextend the writing still further into the margin, this may be done byswinging the stop bar 29 rear- Wardly until the foot plate 38 clears thecontact member'43. This will release the bell crank 41 so that it willbe drawn by the spring 53 into position to free the line lockingmechanism and at the same time the contact member 43 will be broughtinto po sition to engage the front face of the foot plate 38 thusholding the bar 29 in its rearward position so that the platen maycontinue to move until it is brought to rest by a limit stop. Forswinging the stop bar 29 rearwardly a line lock release lever 56 isprovided which is a continuation of the arm 30 upon which the bar 29 issupported. By.

pressing downward upon the lever 56 the bar 29 is swung rearwardly' todisengage the foot plate 38 from the contact member 43, thus releasingthe line locking mechanism.

In order to warn the operator when the platen is approaching the end ofthe line, a signal bell 57 is secured to the lower face of the plate 13and is provided with a tapper clockwise direction, as viewed in Fig. 3,un-.

til the pin 40 has passed the contact finger 62. The tapper will then bereleased and will be swung by the spring 55 and carried by its momentumuntil it strikes the signal bell 50. A pin 64 is provided to engage thetapper arm, near its pivot and impart a. free stroke to the ball at theend of the tapper. The contact finger 62 is provided with a beveled face65 which engages the pin 40 during the reverse movement of the platencarriage and stop bar 29 so that the bar will be deflected outwardly tofree the contact finger 62 on its return movement.

The beveled edge 39 on the foot plate 30 swings the bar 29 outwardly ina similar manner to permit the stop 28 to pass the contact member 43 onthe return movement of the platen in cases where the release lever 56has been operated to permit the stop 28 to pass the Contact member 43for writing in the margin.

I claim:

1.111 a: typewriter, a member having a portion thereof disposed at apoint common to the paths of movement of the type bars, and means forholding said member 7 against movement toprevent printing operationswhen said typewriter approaches the end of a line.

2. In a typewriter, a lever having one arm. thereof arranged at, a pointcommon to the paths of movement of the type bars, a movable platencarriage for said typewriter, and mechanism controlled by said platencarriage for intercepting the opposite arm of said lever to preventprinting operation when said platen carriage approaches a limitingposition.

3. In atypewriter, a platen carriage support movable into and out ofoperating position, a universal member comprising a bell-crank levermounted on said sup-port and movable therewith, a platencarriage on saidsupport, and mechanism mounted on said support and controlled by saidplaten carriage for restricting the movement of said universal member toprevent printing operations of said typewriter when said platen carriageapproaches a limiting position. said mechanism comprising a stop movableinto the path of one end of said bell-crank lever.

4;- In a typewriter, a platen carriage frame having a platen carriagemovably mounted thereon, escapement mechanism for controlling saidplaten carriage, a universal member comprising a. lever mounted on saidplaten carriage frame and having one arm thereof extending into a commonpoint in the paths of the type bars and arranged to be struck by saidbars for actuating said escapement mechanism, and means controlled. bysaid platen carriage for restricting the movement of said universal memher to prevent operation of said escapement mechanism when said platencarriage approaches a limiting position said restricting meanscomprising a stop movable into and out of the path of said lever and aguide for said stop arranged to prevent movement thereof under the forceof the blows of the type bars on said lever.

5. In a typewriter, a platen carriage frame movable into and out ofoperative position, a platen carriage movably mounted on said frame andhaving a platen for holding said lever in positionto check the movementof the type bars of said typewriter to prevent the type from strikingsaid platen, and means controlled by said platen carriage for actuatingsaid holding mechanism to lock said lever when said platen carriageapproaches a limiting position.

6. In a typewriter, a platen carriage frame, a platen carriage movablymounted on said frame, a lever pivoted on said frame and having aportion thereof extending into the path of movement of the type bars ofsaid typewriter so that said lever is actuated by said type bars,escapement mechanism actuated by said lever for con trolling themovement of said carriage, a stop movable into and out of the path ofsaid lever to hold said lever against move ment by the type bars, andmechanism arranged to be operated by said platen carriage as itapproaches a limiting position for shifting said stop to move said stopinto position to hold said lever.

7. In a typewriter, a platen carriage, a stop bar mounted on saidcarriage and movable in one direction out of normal position, a stopcarried by said bar, a signal device having a contact memberarranged tobe engaged by said stop to actuate said device when said platen carriageapproaches a limiting position, and means for swinging said stop bar outof normal position to permit said stop to pass said contact member onthe return movement of said carriage.

8. In a typewriter, a platen carriage frame, a platen carriage movablymounted on said frame, a signal device comprising an arm having acontact member pivoted on said frame, a stop bar pivotally supported bysaid carriage to swing into and out of operating position, andra stop onsaid bar for engaging said contact member to actuate said signal devicewhen said platen carriage approaches alimiting position, said contactmember having a beveled face thereon for engaging said stop on thereturn movement of said platen carriage to swing said bar and stopintoposition to permit said stop to pass said contact niembein,

9. In a typewriter, a platen carriage frame, a platen carriage movablymounted on said frame, line'lock mechanism having a contact member foractuating said mechanism, a signal device having a contact member foractuating said device, a. stop bar movably mounted on said platencarriage and having a stop thereon arranged to successively engage saidcontact members as said platen carriage approaches a limiting position,and means for shifting said stop bar during the return movement of saidcarriage to permit said bar to pass said contact members.

10. In a typewriter, a platen carriage frame, signal mechanism and linelock mechanism mounted on said frame, a platen carriage arranged totravel on said frame, a stop bar movably supported by said carriage andhaving a stop thereon for successively actuating said signal mechanismand said line lock mechanism as said carriage approaches a limitingposition, manually operated means for shifting said stop bar to free thestop thereon from said line lock mechanism, and means for automaticallyshifting said stop bar during the return movement of said carriage topermit the stop thereon to pass said line lock and signal mechanisms.

11. In combination, a platen carriage frame, line lock mechanismcomprising a lil) lever pivotally mounted on said frame, signalmechanism comprising an arm pivotally mounted on said frame, and asingle spring connected with said lever and arm for resiliently holdingsaid lever and arm in their normal positions.

12. In a typewriter, a platen carriage frame, means for supporting saidframe for movement into and out of ope ating position, a platen carriageand platen mounted to travel along said frame, a universal memberpivotally mounted on said frame and having an arm extending into thepath of movement of the type bars, escapement mechanism mounted on saidframe for controlling the movement of the platen thereon, means actuatedby said universal mem her when struck by a type bar for operating saidescapement mechanism, mechanism mounted on said frame for locking saiduniversal member to preventoperation of said escapement mechanism and tointercept the type bars when said platen carriage has moved to aposition to approach the end of a line, a stop bar movably mounted onsaid platen carriage and having a stop thereon for actuating saidlocking mechanism, and means for shifting said stop bar to free saidstop from said locking mechanism to permit further operation of saidtypewriter to print beyond the margin line, i 13. In combination, atypewriter having a platen carriage frame movable into and out ofoperating position, a platen carriage movably mounted on said frame,escapement mechanism on said frame for controlling the movement of saidcarriage, a universal member mounted on said frame for operating saidescapement mechanism and having a portion thereof projecting into thepath of the type bars of said typewriter, a device for locking saiduniversal member to prevent operation of said escapement mechanism andsaid type bars, means mounted on said frame for moving said device intolooking position, signal mechanism mounted on said frame, and a stop barconnected with said carriage and having a stop thereon arranged tosuccessively actuate said signal mechanism and the operating means forsaid locking device as said carriage approaches a limiting position,said escapement mechanism, universal member, locking device andoperating mechanism therefor, signal mechanism, platen carriage, stopbar and stop being all connected with said platen carriage frame andmovable therewith into and out of operating position.

14:, Line lock mechanism for typewriters comprising a pair of bell-cranklevers having pivotally connected arms, a contact member on one of saidlevers for engaging a margin stop, and locking mechanism actuated by theother of said levers to -pre-.

vent writing operation by said typewriter.

15. In a typewriter, a platen carriage frame, a pair of horizontallydisposed bellcranlr levers pivotally mounted on said frame and havingadjacent arms thereof operatively engaging one another, the free arm ofone of said levers being disposed in the path of movement of the stop ofthe platen carriage of said typewriter, and locking mechanism actuatedby the free arm of the other of said bellfcrank levers for preventingwriting operations of said typewriter.

16. In a compactable typewriter, a platen carriage frame having aportion thereof horizontally disposed when said platen carriage frame isin operative position, a platen carriage mounted on said frame andhaving a margin stop thereon, a horizontally disposed bell-crank levermounted on said platen carriage frame and having one end thereofextending into the path of said margin stop, means for limiting themovement of said bel1crank lever, a spring for holding said bell-cranklever at one extremity of its path of movement, a second bell-cranklever pivotally mounted on said platen car riage frame and operativelyengaging the other arm of said first-mentioned bell-crank lever, andline lock mechanism arranged to be actuated by said second bell=cranklever.

17. In a typewriter, a member interposed in the paths of movement of thetype bars at a point common to said paths, and means for holding saidmember against movement to prevent printing operations when said"typewriter approaches the end of a line.

In testimonywhereof I have signed my name to this'specification on this3d day of June, A. D. 1920.

OTTO A. HOKANSON.

